Spacers for cage presses



March 19, 1968 J. w. BURNHAM SPACERS FOR CAGE PRESSES Filed Jan. 27, 1966 INVENTOR.

A TTOFNE'KS'.

United States Patent O 3,373,680 SPACERS FOR CAGE PRESSES John W. Burnham, Piqua, Ohio, assignor to The French Oil Mill Machinery Company, Piqua, Ohio Filed Jan. 27, 1966, Ser. No. 523,357 2 Claims. (Cl. 100-129) ABSTRACT OF THE DISCLOSURE This invention relates to improvements in spacers of the kind used between the cage or screen bars of continuous screw presses which are employed for expressing oil or other liquids from materials containing the same. These spacers are made entirely of stainless steel or other metal having high resistance to corrosion and ample strength to prevent deformation during the pressures to which they are subjected. These spacers comprise a body portion which is of uniform thickness throughout and of the thickness desired between the cage bars, and wedgeshaped pads welded to one side of the body portions of the spacers, and integral projections partly punched out of the body portions to extend into depressions formed in the screen bars.

The cages of presses of this kind are generally composed of separate bars of rectangular cross section extending lengthwise of the cage and spaced apart to form between them narrow, outwardly diverging, drainage slits through which the expressed liquid passes. The cage or screen bars are separated from each other by spacers which hold the bars at correct distances from each other to form spaces of the desired width between adjacent bars, and the spacers also form wedge-shaped spaces between the bars so that the series of bars form a cylindrical cage within which the screw rotates.

It is an object of this invention to provide spacers of this type which are made in two pieces secured together, one piece being made of thin metal to extend substantially throughout the Width of the screen bars, and the other piece or pad being of wedge shape to form a correct spacing of outer portions of the screen bars, so that these bars will be arranged in a cylindrical cage.

It is also an object of this invention to provide the thin pieces of the spacers with projections punched out of them for cooperating with openings in the sides of the screen bars to correctly position the spacers with relation to the screen bars.

- In the accompanying drawings FIG. 1 is an elevation partly in section of a screw press having a cage with bars spaced relatively to each other by spacers embodying this invention.

FIG. 2 is a transverse sectional elevation thereof on an enlarged scale on line 22, FIG. 1.

FIG. 3 is a fragmentary, enlarged, transverse section of the cage showing several of the screen bars with spacers arranged between them.

FIG. 4 is a fragmentary, longitudinal sectional elevation thereof on line 44, FIG. 3.

FIG. 5 is a perspective view of a spacer embodying this invention removed from the press.

FIG. 6 is a face view thereof.

FIG. 1 illustrates an elevation of a screw press having a cage 6 of cylindrical shape formed of screen bars. Within the cage 6 is a worm or screw 7 mounted on a worm shaft 8 which provides rotation of the Worm. One end of the cage is provided with means for feeding material to be acted on into the cage 6 and the other end of the cage is provided with the usual extrusion opening through which the material, after it has been compressed, is disdinal screen bars 13 bearing against the inner edges of the ribs 10. The screen bars are arranged between fixed, longitudinal abutment bars 14, and an adjustable key or clamping bar 15 is provided on each cage section between two abutment bars 16. The key bars 15 may be of wedge shape in cross section and cooperate with abutment bars 16 having inclined faces. Consequently, the key bars can be adjusted for pressing the screen bars toward each other between the abutment bars 14 and 16 in any suitable manner, as for example, by means of screws 17 which may pass through holes in the ribs to enable the screws to draw the key bars outwardly and in cooperation with the abutment bar 16 to crowd the screen bars toward each other between each key bar and the cooperating adjustment bars.

18 represents the spacers which are arranged between adjacent screen bars 13. These spacers must be of such thickness at their inner ends to space the screen bars relatively to each other to the extent desired to provide slits or openings between the screen bars of the width required for passage of the liquid which is being expressed and to exclude most of the expressed material from passing between the screen bars 11. The spacers also must be of a thickness at their outer portions to hold the rectangular screen bars in such angular relation to each other that the screen bars when positioned 'by means of the spacers will occupy positions to form a cylindrical cage.

The spacers may be of different thicknesses depending upon the clearance or widths of slits desired between adjacent screen bars, and to facilitate the manufacture of the spacers they are preferably made in two pieces 20 and 21, the main body portion or piece 20 of the spacer which is substantially coextensive 'With the radial dimension of the screen bar, is made of a flat or sheet material. This is desirable for the reason that flat material of stainless steel or similar material in sheets is being accurately produced in any thicknesses from approximately one-half of a thousandth of an inch to greater thicknesses.

In order to produce a complete spacer, the other piece or pad 21 of the spacer is of a wedge shape with its two flat faces converging toward each other toward the center of the press cage. These two pieces which comprise the spacer are suitably secured together, preferably by weldin so that the path of greatest thickness of the pads 21 of the spacers extends to the outer edge of the thinner plate or body portions 20. The pads 21 may also be made of stainless steel and can be accurately formed in strips and cut crosswise to produce the individual pads 21 of the required length.

In the manufacture of these spacers the differences in width of the spaces between the screen bars is made up entirely by providing the body parts 20 of the spacer of the various thicknesses that may be required, for example, by cutting them from sheets or strips of desired thickness. The other pieces or pads 21 of the spacers may similarly be cut from strips of desired cross section. As a result, a very considerable saving in manufacturing cost is effected by making the body portions 20 entirely from rolled sheets or strips of the required thickness while the other pieces or pads 21 are of a standard, uniform dimenslon.

It is also desirable in connection with spacers to provide means for positioning them in correct relation to the screen bars and this can be readily accomplished by providing each of the body parts 20 of the spacers with projections 24 which may be formed by punching out a semicircular recess in the part 20 of the spacer and leaving the diametrical part of the perforation unsevered and bending it outwardly from the part 20 of the spacer. These projections 24 can thus be formed with a high degree of accuracy to fit into perforations 25 formed in the sides of the screen bars, as clearly shown in FIG. 3. Consequently, when the cage is assembled, the spacers can be readily fitted into the perforations of the screen bars and thus assure a correct locking of each spacer relatively to its screen bar.

The spacers described can be readily made of stainless steel which has a high resistance to compression so that deformation of the spacers due to the pressures exerted on the same by the cage bars is practically eliminated. Furthermore the stainless steel spacers offer a high resistance to electrolysis when exposed to various liquids passed between the screen bars of the press and any distortion of the spacers would cause the screen bars to change their positions so that the distance between some of the bars would be reduced and in others wide open, resulting in an unsatisfactory operation of the press. By means of the spacers herein described such incorrect positioning of the screen bars is avoided so that the press will operate in a uniform manner to avoid neats or foots from squeezing out in larger quantities between pairs of incorrectly positioned screen bars.

By means of the construction described, the manufacture of spacers is facilitated since only the body portions 20 are varied in difierent spacers to provide different sized openings between screen bars, and the pads may all 'be of uniform size. However a correct fit of the screen bars and spacers to constitute a cage may be accomplished as heretofore by the use of shims, not shown, to ensure fit of the 3 screen bars and spacers to form a cage.

It will be understood that various changes in the details, materials and arrangements of parts which have been herein described and illustrated in order to explain the nature of the invention may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.

I claim:

1. Spacers for use in a cage of a continuous screw press having cylindrically arranged screen bars each having a depression in a side thereof, said spacers each being adapted to be positioned between a pair of screen bars, said spacers each made of two pieces, including;

a body portion coextensive with the width and length of the spacer and being of uniform thickness throughout equal to the space desired between screen bars,

a pad of 'wedge shape for positioning between two screen bars at the outer portions thereof and being rigidly secured to one face only of said body portion,

and a projection partly punched and bent outwardly from a side of said body portion and formed integral therewith for entry into a depression in an adjacent screen bar for correctly locating the spacer relatively to said screen bar.

25 2. A spacer according to claim 1 in which said pad is welded to said body, said spacer being formed of stainless steel.

References Cited 30 UNITED STATES PATENTS 2,223,514 12/1940 French 100 129 X 3,093,065 6/1963 French 100 121 3,126,820 3/1964 Upton 100 129 LOUIS O. MAASSEL, Primary Examiner. 

